My message box has been steadily accumulating “Why is John/Martin made of kittens/hedgehogs?” questions for months, and it’s time to admit defeat.
I just don’t know.
I am BAFFLED! I haven’t got a clue! I’m flummoxed! I’m bamboozled! I’m stuck.
But enough misquoting John’s blog, I legitimately do not know. I’ve followed leads, investigated shady corners of the internet, interrogated several people, been pistol-whipped by men in suits (I may have made that one up) and as close as I can figure, the reasoning is simply that Martin Freeman bears some fleeting physical resemblance to both kittens and hedgehogs, and that hedgehogs’ prickly spines are an appropriate metaphor for his scathing sense of humor.
I suspect that like many memes, there is simply no explainable logic to it, but if anyone has anything more concrete, for the love of god, submit it.
In the interest of keeping all my followers up-to-date on the latest Sherlock news, this article invaded Tumblr today and has cause a cavalcade of excitement. It doesn’t explicate a great deal about Series 2, but the phrases “at it for nine months now” and “married or whatever” should sustain the Sherlockians for at least a week or two. Enjoy!
The Stripey Mugs
The stripey mugs nearly broke Tumblr as a result of the sheer volume of crack that they produced. During the filming of series two, this photo was taken on the set (http://vicivefallen.tumblr.com/tagged/on+set) and at some point ended up on Mark Gatiss’s Twitter:

Showing Benedict Cumberbatch and Martin Freeman’s matching mugs full of tea (and revealing that Martin Freeman apparently takes milk in his). With the hiatus getting to them rather pitifully, the fandom spun this photo into its own universe of mug-porn, mug-fanart, mug-replicas, and mug jokes. There is literally fanfiction written about these mugs. It is beyond reason. It is very popular to depict Sherlock and John with these mugs, even though the mugs have never actually been used by the characters. It is unclear whether Martin and Benedict actually picked out matching mugs or if the crew provided them for use on set, but the latter seems more likely.
Examples of mug-obsession to follow.

A Facebook post by Martin Freeman’s long-time girlfriend, tentatively acknowledging the fandom.
Breaking the Fourth Wall (They Know About the Porn)
The phrase “breaking the fourth wall” is used among theatrical types to refer to the imaginary “fourth wall” that separates the actors from the audience. In the case of theater, the edge of the stage generally represents the literal “fourth wall,” and in the case of television, the screen obviously is what separates the action from the audience. To “break the fourth wall” is to do something that causes the actors and audience to acknowledge one another. This can be done either by the audience or by the actors, but usually consists of addressing the audience directly in one way or another.
Regarding the Sherlock fandom, it means that the cast and crew of Sherlock are aware of and somewhat involved with the fandom. Of course, any actors are aware of their fans in general, but the cast and crew of Sherlock have, on multiple occasions, gone out of their way to make fandom-specific references for the benefit of Sherlockians. The first incidence of this came to light in summer of 2011, when a photo surfaced of what is apparently Martin Freeman holding a sign that reads “Te quiero Jan y Rosalia xxx,” (I love Jan and Rosalia), who run a blog about Martin Freeman.

My apologies for the demotivational reframe, this is apparently the default mode of this photo now. Since the photo, there have been multiple troll posts on Tumblr, most notably from Mark Gatiss, good-humoredly acknowledging the insanity of the fandom.

Silly photo of Martin Freeman at the BAFTA awards after winning “Best Supporting Role” for depicting John Watson in Sherlock. The photo has been edited to make it appear that he is very chuffed about jam, rather than his award.

